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<H1>coroutine</H1>
Switches on the coroutine flag, equivalent to set_flag(coroutine, on).


<H3>This built-in predicate is obsolete!</H3>
<H2>Description</H2>
   Used to switch the global coroutine-flag to on.  This causes a subset of
   the built-in predicates not to raise instantiation faults any longer but
   to delay instead.  This concerns all sufficiently logical predicates
   like the arithmetic built-ins, functor/3, arg/3, and many others.

<P>

<H3>Modes and Determinism</H3><UL>
<LI>coroutine is det
</UL>
<H2>Examples</H2>
<PRE>
[eclipse 1]: X&gt;0.
instantiation fault in X &gt; 0
[eclipse 2]: coroutine.

yes.
[eclipse 3]: X&gt;0.

X = X

Delayed goals:
        X &gt; 0
yes.



</PRE>
<H2>See Also</H2>
<A HREF="../../kernel/env/set_flag-2.html">set_flag / 2</A>
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